InsFluid-WGC57.139 - Insulating Fluids - DGA in LTC Working Group

This guide discusses and recommends methods of testing and evaluating dissolved gases in mineral based transformer oils found in Load Tap Changers (LTCs). General types of LTC mechanisms, breathing configuration and electrical design will be included as evaluation criteria in determining when mechanical damage or failure can occur. Dissolved Gas Analysis (DGA) provides a non-invasive means of signaling when maintenance of the LTC is required. This guide will provide the information needed to develop a baseline health curve for any type of equipment covered within and will provide basic gassing levels. Ultimately, the user must set their own standards based on local conditions.